The reaction of OH radical with CO was investigated by time-resolved Fourier transform infrared (TR-FTIR) spectroscopy. OH radical was produced by laser photolysis of HNO3 at 248 nm. IR emission from vibrationally excited unsymmetric stretching mode (nu(3)) of product CO2 was observed for the first time (Fig. 2). The simulated results for the IR emission spectrum Of CO2 shows that the CO2 populates up to v = 6 and the quantum number v = 2 is the most populated vibration level (Fig. 4). Comparison of the experimental distribution results of product CO2 with quantum or QCT calculation by Schatz and co-workers shows that experimental distributions agree well with the quantum predicting but is different from that of the QCT calculation. This consistency suggests that the SFH potential surface (Fig. 1) is accurate and the quantum dynamics method but not QCT is proper approach for the chemical reaction involving H atom leaping.